Reasons for a film on the dishes include too much detergent, unsuitable water temperature or hard water minerals. If the film will not come off when washed by hand, it could be a permanent etching caused by soft water and excessive heat or too much detergent.Continue Reading
To ensure that the glasses or dishes are not damaged by etching, ensure that the water going to the dishwasher is no hotter than 140 degrees Fahrenheit, and do not use extra-hot settings. Do not pre-rinse dishes, as this can actually make it harder for the detergent to clean the dishes and make sure not to use too much detergent in the machine.
If the film comes off when washing it with hot water, adjust the amount of detergent being used and check that the water heater is providing water at the temperature required by the machine. Adding a rinse aid or rinse additive into the machine helps water drain in thin sheets rather than in droplets. Its purpose is to prevent spotting on glassware which can leave limescale on the glass.
The limescale deposits are due to hard water areas and this can be combated by using a hard water cleaner for dishwashers as well as using a rinse aid. Acidic additives to the detergent can also help keep glassware shining.Learn more about Dishwashers